The present invention relates generally to a system and method for detecting biohazard materials in mail handling systems and, more particularly, to a system and method that detects biohazard materials, especially particulates, in mail handling systems at that point or points in the handling process having the greatest probability of expelling or expressing the biohazard material into the ambient air.
Mail of the type characterized xe2x80x9cletterxe2x80x9d mail, i.e., mail that is contained within envelopes of various sizes is processed by mail handling and sorting machines that transport the individual xe2x80x9cpiecesxe2x80x9d using various types of conveyers, drive rollers, pinch rollers, belts, and the like to move the pieces along various tracks, chutes, and paths while address information is being scanned to allow sorting and routing of the piece.
Some mail pieces have been known to contain dangerous biohazard materials, including particulates, such as anthrax spores. In addition to seeking to expose the addressee to the biohazard material, the biohazard-containing piece also contaminates other mail pieces being handled in the mail transport system and also contaminates the machinery, vehicles, and physical plants that are used to process the mail.
U.S. Published application Ser. No. US 2002/0126008 published Sep. 12, 2002 and filed Oct. 31, 2001 discloses use of sensors at various locations within a typical mail processing system to sense the presence of a harmful agent. This system is completely open to the ambient atmosphere. (The present application is based upon a provisional patent application filed Oct. 31, 2001.)
U.S. Published application Ser. No. US 2002/0124664 published Sep. 12, 2002 and filed Feb. 1, 2002 discloses use of a mail sampling system used in a room separate from the remainder of a post office facility and in which there is an air intake fan and all outgoing air is filtered before release. Most often openings are formed in the parcels and mail for the sampling. The sampling system is said to determine whether mail is contaminated with a chemical or biological agent. (The present application is based upon a provisional patent application filed Oct. 31, 2001.)
U.S. Pat. Nos. 5,942,699 and 6,324,927 disclose a manner of collective sampling of cargo items for contaminants such as chemical residues. The cargo items are placed into a special airtight chamber and physically agitated, such as by vibration, to release particulates and vapors from the items, and bursts of high pressure air is sent into the chamber. Heated air may also be used.
U.S. Pat. No. 3,915,339 discloses use of pressurized air into a container to loosen and cause free flow of material therein move.
U.S. Pat. No. 3,998,101 discloses a method and apparatus for sampling the atmosphere in non-hermetically-sealed containers by enclosing baggage in a chamber and varying the air pressure cyclically to mix a portion of the air in the baggage with the air in the chamber and a vapor detector is used to detect the presence of explosives or drugs in the baggage.
U.S. Pat. No. 4,580,440 discloses a method of detecting a contraband substance in freight cargo in which the container is agitated to disturb particulates therein and samples are taken of the air containing such particulates. The collected particulates are heated to drive off vapors indicative of the contraband substance and the vapors are analyzed in a mass analyzer.
U.S. Pat. No. 4,718,268 discloses a method and apparatus for detecting a contraband substance in freight cargo similar to that of U.S. Pat. No. 4,580,440 mentioned above.
U.S. Pat. No. 4,764,351 discloses a sterilization method and apparatus using a gaseous agent for sterilizing a gas for use in treating materials.
U.S. Pat. No. 5,322,603 discloses a method of an apparatus for treating infections medical wastes is which large sizes of medical waste in a sealed body are exposed to microwaves and heat.
U.S. Pat. No. 5,470,546 discloses apparatus for storing and sterilizing bio-hazardous waste in which air is evacuated and pressurized steam is injected.
U.S. Pat. No. 5,591,117 discloses a method and an apparatus for the disposal of material containing infective microorganisms such as bacteria, fungi and viruses by introducing the material into a container which can be charged with ozone and exposed to the action thereof until the microorganisms are killed, and then the ozone is discharged from the container and converted to a lower valence level and the container is then evacuated.
U.S. Pat. No. 5,700,426 discloses a method for decontaminating or sterilizing xe2x80x9cin situxe2x80x9d a vacuum sealed container and device for implementing such method for sterilizing or decontaminating microorganisms or dangerous products.
U.S. Pat. No. 5,841,038 discloses a remote sampling device for possibly hazardous content of a container. A hollow needle punctures the container and is used to withdraw the contents or to introduce another substance. An inert gas can be introduced into the area where the needle punctures the container.
U.S. Pat. No. 5,859,362 discloses a trace vapor detection method and device of sampling a volume of air suspected of containing drug vapors, removing particulate matter and binding vapors of the drug for further analysis. The device has a sampling, filtration and vacuum port components.
U.S. Pat. No. 6,159,422 discloses methods and apparatus for the treatment of hazardous biological waste materials. A biological waste material is placed into a chamber and a vacuum applied. Water vapor is introduced into the chamber and electromagnetic radiation energy is applied to produce a plasma.
U.S. Pat. No. 6,183,950 discloses a method and apparatus for detecting viruses using primary and secondary biomarkers. There is a sampling section for sampling the atmosphere and includes an intake device for taking a sample. It includes a heater for distilling any cholesterol and/or fatty acids from the sample. There is an analysis section for determining whether cholesterol and/or fatty acids that are indicative of the likely presence of a virus in the sample are present.
U.S. Pat. No. 6,295,860 for explosive detection system and sample collecting device in which luggage enters the device and leaves the device after inspection in which a vapor leaking from the luggage is sampled by a sampling probe, negative corona discharge is used to ionize the vapor, and a mass spectrometer is used to detect the ionized vapor to determine whether or not an explosive is present.
Patent Abstracts of Japan Pub. No. 02159554 A published Dec. 12, 1988, Application No. 63313358 discloses a monitoring method of a pathogen or allergen in which a biosensor is provided near a suction port for air conditioning provided for each room of wall surface which tends to gather mold.
WO 91/09307 published Jun. 27, 1991, for Explosive Detection Screening System detects vapor or particulate emissions from explosives and other controlled substances and reports their presence and may also report the concentration. There is a sampling chamber for collection of vapors or other controlled substances and a concentration and analyzing system, and a control and data processing system for the control of the overall system. There are a number of U.S. Pat. Nos. in this series, including the following: U.S. Pat. Nos. 4,987,767; 5,109,691; 5,345,809; 5,465,607; and 5,585,575.
Because of the huge volume of mail sent daily, a piece-by-piece inspection of the mail is not economically feasible; however, a system that detects the presence of a biohazard-containing mail piece within a few seconds of its passing through a process point would greatly simplify the identification of a biohazard-containing mail piece as well as that sub-set of mail pieces that may have likewise have been contaminated.
In view of the above, the present invention provides a system and method for detecting biohazard particulates in mail handling systems that detects the presence of a biohazard material shortly after the mail piece has been processed through machinery that functions to squeeze or compress the mail piece to expel at least some of the air in the interior volume of the mail piece and at least some of the materials therein.
Thus individual mail pieces are subjected to a squeezing or compressing action to expel some of the interior air from the mail piece and any contaminants therein at a location which is preferably as close as reasonably possible to the beginning of the mail handling and sorting line. In one preferred form, the mail handling system includes drive rollers, pinch rollers, or belt conveyors that serve to compress each individual mail piece to force at least some of the air in the interior volume of the mail piece and any material or particulates contained therein from the mail piece.
A forced air flow hood or plenum is located adjacent the mail handling system to aspirate some of the air and any air entrained materials or particles from the mail pieces as they are processed through the drive rollers, pinch rollers, or belt conveyors. The aspirated air is provided to a biohazard detection device such as a sensor suite.
The present invention advantageously provides a system and method of detecting biohazard particulates in mail handling systems.
Other features and advantages will be apparent from the following detailed description of preferred embodiments taken in conjunction with the accompanying drawings.